Good, but not great.
Had high expectations the first time we went. We've been twice. The animatronic dinosaurs are pretty cool (beware if you have babies/toddlers as they usually scream and cry out of fear of the roaring). The kids area is neat. Best part for my kids was the paleontological dig zone in the kids area (inside the back room - go through the dinosaur room and you'll find it).
It was much smaller than I thought it would be, so that was disappointing. But there are some interesting things to see there. Worth at least 1 visit. Only went a 2nd time because it was Nevada Science Week and it was a free event - got to meet a bunch of scientists and found out about a group that goes on digs! That was definitely worth it.